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目的:对比分析G1、G2级胰腺神经内分泌肿瘤(pNEN)的MRI征象,探讨“主胰管绕道征”的诊断价值。方法:收集32例pNEN患者的临床资料,以术后病理学检查为金标准,定量分析G1、G2级临床指标及影像学指标的差异,并着重分析pNEN与主胰管的关系。结果:32例患者中,病理分级G1、G2、G3级的患者分别有12例、16例、4例,分别以胰尾、胰头、胰颈为主要发生部位。与G1级神经内分泌瘤(NET)相比,G2级NET肿瘤直径显著增大,不规则形态的病灶增多,边缘模糊,生物学行为出现明显恶性倾向,主胰管扩张、胰腺外侵犯及淋巴结/肝转移的发生率升高。G1级NET的MRI平扫信号均质程度高于G2级(P<0.05),但二者在增强MRI扫描的各个期象信号强度均无明显差异(P>0.05)。28例NET患者中,22例(78.6%)出现主胰管绕道征;神经内分泌癌(NEC)患者无一例出现此征象。术前,28例NET的诊断准确率为78.6%(22/28),存在6例误诊,其中,3例误诊为胰腺癌,2例误诊为囊腺瘤(癌),1例误诊为胰腺假性囊肿。在原MRI诊断依据的基础上纳入“主胰管绕道征”,诊断准确率提高至89.3%(25/28),但仍存在3例误诊,其中2例误诊为囊腺瘤(癌),1例误诊为胰腺假性囊肿,排除了胰腺癌的误诊。结论:MRI对鉴别诊断良恶性pNEN有较高的准确性,但对部分G1与G2级NET仍存在一定的误诊率,主胰管绕道征可帮助减少出现胰腺癌误诊。  相似文献   
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Arylamine N-acetyl transferase (NAT2) displays extensive genetic polymorphisms that affect the rates of acetylation of drugs and genotoxic compounds such as amine carcinogens. To investigate whether the slow acetylator genotype is a risk factor for development of bladder cancer following schistosomal infection of the urinary tract, the authors determined the frequencies of 3 common polymorphisms in the NAT2 gene (341T>C, 590G>A, and 282C>T), which are associated with impaired acetylation activity, in control subjects (n=61; mean age 34.3+/-9.2 years) and in schistosomiasis-associated bladder cancer patients (n=55; 52+/-10.9 years) from the Egyptian population. Genotyping was carried out using rapid cycle PCR on the LightCycler, and subjects were assigned to a slow, intermediate, or rapid acetylator phenotype on the basis of the genotypes. The frequencies of the mutant alleles observed in the controls from the present study were similar to those reported previously for both the Egyptian population and other Arab populations. Patients showed a higher prevalence (78.2%) of slow acetylator phenotype than controls (67.2%), but this did not reach statistical significance (P=0.19). However, there were significantly more individuals who were carriers of 2 mutant 341T>C alleles (NAT2*5/*5 genotype) in the patient group compared with controls (odds ratio 2.6, CI 1.02-6.67, P=0.026). The alloenzyme encoded by this allele has been shown to display a large reduction in its catalytic activity. In conclusion, these data suggest that the NAT2*5/*5 genotype is a potential risk factor for development of urinary bladder cancer in patients with prior schistosomiasis infection.  相似文献   
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OBJECTIVES: To evaluate women's experience of giving consent to obstetric and gynaecological surgery and to examine differences between those undergoing elective and emergency procedures. DESIGN: A prospective questionnaire study. SETTING: A large teaching hospital. POPULATION: 1006 consecutive patients undergoing elective or emergency surgery in obstetrics and gynaecology. METHODS: Questionnaires were administered to women who had given consent to surgery following the introduction of national guidelines and consent form. Differences in responses between elective and emergency patients were assessed using frequencies, single and multivariable analyses. MAIN OUTCOME MEASURES: Patients' experience and recall of the consent process, their overall satisfaction and their views on what is important for adequate consent. RESULTS: There were significant differences between patients undergoing elective or emergency surgery. Patients undergoing emergency surgery were less likely to have read (OR 0.22) or understood (OR 0.40) the consent form, and were more likely to report feeling frightened by signing it (OR 2.52). They were more likely to report they felt they had no choice about signing the consent form (OR 2.11), and that they would have signed regardless of its content (OR 3.14). Overall, significantly more patients undergoing elective (80%) or emergency (63%) surgery reported satisfaction with the consent process. Patients were more likely to report satisfaction if they read (OR 1.80) and agreed with (OR 3.49) the consent form, and if someone checked that they understood (OR 3.09). CONCLUSION: Patients' needs may not be adequately addressed by current guidelines for consent to treatment, particularly in emergency circumstances. The introduction of more complex forms and procedures appears to conflict with patients' need for personal communication and advocacy. The implications on the ethical and legal standing of consent are considerable.  相似文献   
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Sodium ibuprofen (Ibu-Na) and different ibuprofen-amino acid compounds, lysinate (Ibu-Lys), arginate (Ibu-Arg) and histidinate (Ibu-His), were evaluated for emulsifying, haemolytic and cytotoxic properties. The highest reduction of surface tension was obtained with Ibu-Lys which shows good emulsifying qualities. At the same time, Ibu-Lys reveals the highest haemolytic activity and affects porcine cornea integrity. However, incorporation of Ibu-Lys into an emulsion system significantly decreases haemolysis. On the contrary Ibu-Arg, which shows a lower surface tension reduction, allows, unlike Ibu-Na and Ibu-His, for comparably stable emulsions with comparable erythrocyte damage.  相似文献   
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Retinitis pigmentosa (RP) is a group of human retinal disorders, with more than 100 genes involved in retinal degeneration. Canine and murine models are useful for investigating human RP based on known, naturally occurring mutations. In Schapendoes dogs, for example, a mutation in the CCDC66 gene has been shown to cause autosomal recessively inherited, generalized progressive retinal atrophy (gPRA), the canine counterpart to RP. Here, a novel mouse model with a disrupted Ccdc66 gene was investigated to reveal the function of protein CCDC66 and the pathogenesis of this form of gPRA. Homozygous Ccdc66 mutant mice lack retinal Ccdc66 RNA and protein expression. Light and electron microscopy reveal an initial degeneration of photoreceptors already at 13 days of age, followed by a slow, progressive retinal degeneration over months. Retinal dysfunction causes reduced scotopic a-wave amplitudes, declining from 1 to 7 months of age as well as an early reduction of the photopic b-wave at 1 month, improving slightly at 7 months, as evidenced by electroretinography. In the retina of the wild-type (WT) mouse, protein CCDC66 is present at highest levels after birth, followed by a decline until adulthood, suggesting a crucial role in early development. Protein CCDC66 is expressed predominantly in the developing rod outer segments as confirmed by subcellular analyses. These findings illustrate that the lack of protein CCDC66 causes early, slow progressive rod-cone dysplasia in the novel Ccdc66 mutant mouse model, thus providing a sound foundation for the development of therapeutic strategies.  相似文献   
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